[Serusers] Server error

i have a 6 line SIP phone. Its IP address is 192.168.1.159. Im placing a call to 5555 ( another line on the same phone). I have set the proxy for both the lines to my SERs IP address (192.168.1.240).I havent enabled register with proxy on the phone but i tried that before and that gave me the same server error as the one mentioned below. These are the packets that i have captured while making the call. Now the problem is that I am unable to understand the kind of internal error it is giving. 18 6.670873 192.168.1.159 192.168.1.240 SIP/SDP Request: INVITE sip:5555@192.168.1.240, with session description 19 6.671179 192.168.1.240 192.168.1.159 SIP Status: 100 trying -- your call is important to us 20 6.732622 192.168.1.240 192.168.1.159 SIP Status: 500 I'm terribly sorry, server error occured (2/TM) 21 6.801520 192.168.1.159 192.168.1.240 SIP Request: ACK sip:5555@192.168.1.240 Also the SIP message header of Packet 20 , as shown below, talks about warning 392. Does anyone know what warning it is? FRAME 20: Session Initiation Protocol Status line: SIP/2.0 500 I'm terribly sorry, server error occured (2/TM) Message Header Via: SIP/2.0/UDP 192.168.1.159:5060 From: "in2" <sip:in2@192.168.1.240>;tag=00036b3c33b500071afb6b0a-38f8c47a To: <sip:5555@192.168.1.240>;tag=a6a1c5f60faecf035a1ae5b6e96e979a-188d Call-ID: 00036b3c-33b50007-2047443d-0967cdd3(a)192.168.1.159 CSeq: 101 INVITE Server: Sip EXpress router (0.8.11 (i386/linux)) Content-Length: 0 Warning: 392 192.168.1.240:5060 "Noisy feedback tells: pid=925 req_src_ip=192.168.1.240 req_src_port=5060 in_uri=sip:5555@192.168.1.240 out_uri=sip:5555@192.168.1.240 via_cnt==112" I have attached my ser.sfg for your reference. TIA, Urvish Khandwalla